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Soil Science

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A Manometric Method For The Determination Of Soil Carbonates In The Field, N. A. Polyzopoulos May 1959

A Manometric Method For The Determination Of Soil Carbonates In The Field, N. A. Polyzopoulos

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In soil survey work the method now generally used to evaluate the carbonate content of the soil in the field is to observe the amount of effervescence that takes place when the soil reacts with dilute acid. The four degrees of effervescence usually recognized are designated by the symbols eo, e, es, ev and correspond roughly to a lime content of 0-0.5, 0.5-3, 3-15, and above 15 per cent, respectively. This, or course, is a very rough estimate and therefore a method is needed for the quantitative determination of carbonates in the field with a fair degree of accuracy. If …


Development And Evaluation Of Laboratory Methods For Determining The Nitrogen Supplying Power Of The Irrigated Soils Of Northern Utah, Jerald Ross Wight May 1959

Development And Evaluation Of Laboratory Methods For Determining The Nitrogen Supplying Power Of The Irrigated Soils Of Northern Utah, Jerald Ross Wight

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Nitrogen is the most widely needed and the most widely used of the fertilizer elements. Yet, in spite of the voluminous research work of evaluating the nitrogen status of soils, laboratory tests for the purpose of predicting need of nitrogen fertilizer are not very widely used. In general, laboratory tests for nitrogen supplying power have not given satisfactory results. Methods currently employed by a few laboratories can be classified either as biological or chemical. In the former method, the soil is incubated under optimum conditions and the amount of nitrate released over a given period of time is measured and …


An Application Of A Thermodynamic Flow Equation To Water Movement In Unsaturated Soil, Brennan Derry Soane May 1958

An Application Of A Thermodynamic Flow Equation To Water Movement In Unsaturated Soil, Brennan Derry Soane

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The movement of water in soil presents many interesting problems to the research worker. It is also a subject which finds wide and important application in agriculture and several branches of engineering.

The object of this work was to examine the usefulness of a new equation of flow of water in unsaturated soil. If valid, this new approach may be able to eliminate some of the gaps in our present knowledge of the subject.

All soil lying above the capillary fringe of a water table is in the unsaturated state with respect to water. This means that in any macroscopic …


The Effect Of The Bicarbonate Ion On The Respiration Of Excised Roots, Gene W. Miller May 1954

The Effect Of The Bicarbonate Ion On The Respiration Of Excised Roots, Gene W. Miller

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

For many years man has been searching for a cure for lime-induced chlorosis. This disease is prevalent throughout the entire western United States and is characterized by a yellowing of the leaves, destruction of the chlorophyll, and eventual death of the plant. It has brought devastation of fruit orchards in Utah, costing fruit producers millions of dollars. Hardly any county in Utah is free from this destructive nutritional disease.


Effect Of Stubble Mulching On Number And Activity Of Earthworms, S. P. Teotia, F. L. Duley, T. M. Mccalla Sep 1950

Effect Of Stubble Mulching On Number And Activity Of Earthworms, S. P. Teotia, F. L. Duley, T. M. Mccalla

Nebraska Agricultural Experiment Station: Historical Research Bulletins

A survey of earthworm population under different cropping systems was made under stubble mulch farming and where the residue was plowed under. The influence of earthworms on some of the important physical and biological properties of the soil was studied. Their role in the decomposition of crop residues was also determined.


Microorganisms And Soil Structure, T. M. Mccalla Mar 1950

Microorganisms And Soil Structure, T. M. Mccalla

Department of Agronomy and Horticulture: Faculty Publications

SUMMARY

Laboratory tests were made to determine the effectiveness of different compounds and microbial groups in increasing the stability of Peorian loess lumps against the action of falling water drops. The influence of these on percolation tests in the laboratory was also determined.

Many organic substances-dextrose, sucrose, starch, peptone, cullulose, and gum arabic-did not themselves contribute directly to soil-structure stability, though these substances do furnish energy material for soil microorganisms, which can convert them readily into either microbial tissue or decomposition products that increase soil-structure stability. Lignin, proteins, oils, fats, waxes, resin, and paraffin increased the stability of lumps of …


Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel Aug 1943

Nitrate Production As Affected By Grain-Crop Residues On The Surface Of The Soil, T. M. Mccalla, J. C. Russel

Nebraska Agricultural Experiment Station: Historical Research Bulletins

The purpose of this bulletin is to present the data on nitrate contents and nitrate production in tests where straw or stalk residues were left on the surface through subsurface tillage, as compared with check treatments where these residues were plowed under or were absent. Nine of these tests were at Lincoln, Nebraska, and one was at the Hastings, Nebraska, Hydrological Project. Two tests were conducted in 1939, four in 1941, and four in 1942.


Vegetation Of The Northern Part Of Cherry County, Nebraska, William L. Tolstead Jul 1942

Vegetation Of The Northern Part Of Cherry County, Nebraska, William L. Tolstead

Conservation and Survey Division: Faculty and Staff Publications

Agricultural practices in the Great Plains of North America are now in a period of adjustment from a traditional agriculture initiated by pioneer farmers to a grazing economy based upon potentialities of climate and soil. The attainment of a proper system of land use has been retarded in many localities by the lack of definite information concerning the vegetation and its indicator significance. In this study of the vegetation of Cherry County, Nebraska, the interrelations between the plants and their environments are discussed, the dominant species are described, and changes in grasslands caused by seasons, grazing, and climatic cycles are …


The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding Jun 1941

The Geographic Distribution Of Azotobacter And Rhizobium Meliloti In Nebraska Soils In Relation To Certain Environmental Factors, H. B. Peterson, T. H. Goodding

Nebraska Agricultural Experiment Station: Historical Research Bulletins

In this investigation a survey of Nebraska soils has been made in order to determine the distribution of the aerobic nonsymbiotic and symbiotic nitrogen fixers of the genera Azotobacter and Rhizobium respectively. In connection with this survey, some of the characteristics of the soils which may bring about this distribution were studied. Up to this time practically no research has been reported on the microflora of the soils of Nebraska. Hence there is little basis for predicting the activity of these organisms under environmental conditions as they exist here. It is hoped that this work will not only supply some …


Effect Of Organic Matter Decomposition On The Solubility And Fixation Of Phosphorus In Alkaline Soils, H. F. Rhoades Jun 1939

Effect Of Organic Matter Decomposition On The Solubility And Fixation Of Phosphorus In Alkaline Soils, H. F. Rhoades

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is the purpose of this bulletin to report a laboratory study on the effects of organic matter decomposition on the solubility and fixation of phosphorus in alkaline soils. The study included the following: (1) a comparison of the effects of a decomposing organic material with those of a physiologically acid nitrogen fertilizer, and (2) a comparison of the effects of different organic materials of varying phosphorus contents.


An Outline Of The Principal Natural Resources Of Nebraska And Their Conservation, George E. Condra Jan 1939

An Outline Of The Principal Natural Resources Of Nebraska And Their Conservation, George E. Condra

George E. Condra Publications

Nebraska is well endowed with important natural resources, such as stone, clay, sand, soil, water, prairie, forests and wildlife. However, soil and water are our basic heritage because they, more than other resources, support native life, agriculture, industry, and social development.


An Outline Of Nebraska's Industries, George E. Condra Jan 1939

An Outline Of Nebraska's Industries, George E. Condra

George E. Condra Publications

The principal industries of Nebraska are summarized into the following groups: mineral, agriculture, manufacturing, transportation and publishing, and trade or mechandizing.


A Proposed Method For Classifying And Evaluating Soils On The Basis Of Productivity And Use Suitabilities, Arthur Anderson, A. P. Nelson, F. A. Hayes, I. D. Wood May 1938

A Proposed Method For Classifying And Evaluating Soils On The Basis Of Productivity And Use Suitabilities, Arthur Anderson, A. P. Nelson, F. A. Hayes, I. D. Wood

Nebraska Agricultural Experiment Station: Historical Research Bulletins

It is the object of this paper to present a method for classifying and evaluating the soils as mapped in regular soil surveys on the basis of land types, which are here defined as areas having reasonably similar productivity and use suitabilities. The standards used to differentiate land types will vary according to the desired objectives, but any material difference in yield, or in practices necessary to maintain a desirable level of productivity will justify recognition of land types. The proposed procedure involves a more detailed study of the influence which soils, slope, erosion, and drainage have on specific crops …


Infiltration And Capillary Rise In Sandy Soils, Wallace M. Johnson Apr 1938

Infiltration And Capillary Rise In Sandy Soils, Wallace M. Johnson

Journal of the Minnesota Academy of Science

No abstract provided.


Characteristics Of Some Forest Soils Developed On The Young Red (Patrician) Drift, C. O. Rost, Olaf C. Soine Apr 1938

Characteristics Of Some Forest Soils Developed On The Young Red (Patrician) Drift, C. O. Rost, Olaf C. Soine

Journal of the Minnesota Academy of Science

No abstract provided.


The Sugar Beet Industry Of Nebraska, Esther S. Anderson Apr 1935

The Sugar Beet Industry Of Nebraska, Esther S. Anderson

Conservation and Survey Division: Faculty and Staff Publications

No abstract provided.


The Relation Of Drouth To Water-Use In Nebraska, G. E. Condra Nov 1934

The Relation Of Drouth To Water-Use In Nebraska, G. E. Condra

George E. Condra Publications

Three severe drouths have occurred in Nebraska and adjacent states within the past eighty years, and less severe ones have come at moderately regular intervals. Their influence on the agricultural development of the state is well known, but their relation to water supply in general is not so well understood. This paper is a brief review of the relation of drouth to soil moisture, surace water, and groundwater supplies.


The Relation Of The Native Forest Cover To The Physical And Chemical Nature Of The Soils Of The Mammoth Cave National Park Area, Sheppard Walker Aug 1933

The Relation Of The Native Forest Cover To The Physical And Chemical Nature Of The Soils Of The Mammoth Cave National Park Area, Sheppard Walker

Masters Theses & Specialist Projects

This study was undertaken for the purpose of determining the relation existing between the native forest cover and the chemical and physical properties of the soils of the Mammoth Cave National Park area. The study was suggested by certain references in the literature to a correlation existing between forest cover and the geological, chemical and physical nature of soils of this area. The recent attempt at reforestation in the Mammoth Cave National Park area renders such a study timely, and it is believed that the results reported in this paper will materially aid the Mammoth Cave National Park Commission and …


The Effect Of Soil Moisture On The Establishment Of Spruce Reproduction In British Columbia, Percy Munson Barr Jan 1930

The Effect Of Soil Moisture On The Establishment Of Spruce Reproduction In British Columbia, Percy Munson Barr

Yale School of the Environment Bulletin Series

Most of the field work has been conducted at the Aleza Lake Forest Experiment Station, in the valley of the Upper Fraser River, near the city of Prince George [British Columbia].

I. A series of twelve permanent plots (numbers 1 to 12) was established for the purpose of studying the occurrence of natural reproduction on various types of seed bed, under different densities of overwood and on northern and southern aspects. 2. A second series of four plots (numbers 17 to 20) was laid out in logged-off land for the purpose of studying the survival and growth of advance reproduction …


Some Aspects Of Soil Moisture In The Forest, Ian J. Craib Jan 1929

Some Aspects Of Soil Moisture In The Forest, Ian J. Craib

Yale School of the Environment Bulletin Series

By determining the moisture content of carefully selected soil samples taken at various depths down to three feet, the moisture content of soils in the forest and in the open have been compared. The soils investigated were similar in their mechanical properties. Part I is an investigation of the effect of forest cover on the amount of water in the soil over the growing season and its availability. Part II is an investigation of the effect of root competition on the available water supply of forest soils.